The known dyeing padder--a dyeing vat for a dye bath with a squeezing mechanism--consists of a simple roller vat, wherein the warp to be dyed is impregnated by being guided, deflected and finally squeezed via several cylinders or rollers and/or deflection rollers located under the level of the dye bath. The path travelled by the warp in the dye bath is determined by the number of the mentioned immersed rollers and deflection rollers and the distance between them. Since the dyeing speed is predetermined in the case of indigo dye and is practically never changed, the immersion time is constant and depends solely on the construction of the dyeing vat. But now the market demands a variety of shades of indigo denim and also other colors. However, in other colors, such as "black denim" or "color denim", only a very poor quality can be obtained with the conventional indigo dyeing vats. Other colors are dyed with other dye groups, mostly sulfur dyes or vat dyes. These, and also other cotton dye groups, such as reactive and direct dyes, have a considerably higher affinity to cotton than indigo. When using the conventional dyeing vats (dyeing troughs, dyeing becks or dyeing chassis) with other affinity dyes a strong color drain also called "shading" results. Due to the affinity, the dye is "extracted" from the dye bath, and the batch is more strongly colored at the beginning than at the end, a phenomenon which is also called "head-tail" drain. This is a very undesirable dyeing effect, since it can appear over several thousand meters of the materials to be dyed, which then becomes seconds.
In the piece-dyeing process (dyeing of fabrics) it is known and usual to consider dyeing vats with a very small content of dye bath, the socalled "saving vats". These baths can contain only 40 1 or less of dye bath. It is also known in the piece-dyeing process to displace the dye bath in normal dyeing vats with so-called displacement bodies. However, these special dyeing vats also have the disadvantage of very short immersion paths. Also, another common feature is that their immersion path is predetermined and cannot for instance be cut in half or doubled, unless the goods to be dyed are taken out and then reintroduced in the dyeing vat in such a way that rollers are skipped or previously skipped rollers are used. This is fairly simple in the case of woven goods, but becomes very complicated affecting quality of warps consisting of several thousand individual threads.